This invention relates to apparatus for testing the stretch of a sample of fabric, and more particularly to a hand-held stretching device.
The amount of stretch of the fabric is an important consideration in manufacturing garments. The need for a particular amount of stretch requires basic consideration in the early development stages, such as when choosing the fiber or yarn type. There are a number of different methods for measuring stretch, such as applying a known force to put the fabric in tension, as with a standard weight, and then measuring the percent increase in length of the fabric.
By far the most often used test, however, is the "hand stretch" method, whereby the fabric is simply pinched between the fingers and pulled until near maximum stretch is reached. If accuracy is required, a ruler is used to measure the increased length. The major drawback, of course, to this method is the poor correlation to the objective laboratory methods, or even to different persons making the tests. The great advantages of this method are that it is convenient, inexpensive, quick and portable. Thus, what is desired is a device which will elongate a given fabric sample to determine its stretch propensity, quantify this stretch at a pre-determined load, and retain the fabric in a stretched state for a specified period of time, whereupon relaxation the percent unrecovered stretch can be measured.